THE OAK-PRUNER. 89 
in April, they were from 4 to 5 mm long. They ate the wood under the bark, follow- 
ing its grain, and packed their burrows solidly with their dust. The growth and 
progress were both slow, for by the next April they had scarcely more than doubled 
in length and had not traveled more than from 4 to 6 inches during the year; but 
after July they developed an euormous appetite and consumed the wood for at least 
an inch in length and often entirely around the limb, ejecting their castings through 
holes made in the bark. When full fed they bore obliquely an oval hole into the 
wood, penetrating it from 4 to 10 inches. The larva then packs the opening with 
fin© castings and enlarges a couple of inches of the interior of the burrow by gnaw- 
ing off its sides a quantity of coarse fiber, in which it lies, after turning its head to 
the entrance. When about to become pupa (I witnessed the process) the skin rup- 
tures on the dorsum of three or four segmeuts next the head ; the head of the pupa 
appears, and after about half an hour's wriggling the whole body is divested of its 
covering. To the observer the pupa appears to crawl out of the skiu, but in fact the 
skin with the large mandibles is forced backwards by the alternate extension and con- 
traction of the segments, assisted materially by the fiber that surrounds it. After 
its soft body hardens the same movements free it from the fiber, some being shoved 
in advance of the head, and some posteriorly, the exuviae being often found at the 
distal end of the hole. The time spent in the pupal state is indefinite and does not 
seem to concern greatly the time of the appearance of the beetle. Sticks split open 
at different periods from December till March contained larvae and pupae about equally, 
but no developed beetles. A larva that I observed go into the wood in April appeared 
as a beetle among the first of such as had presumably pupated in the fall. 
The number of these beetles obtained that and the present season was great and 
afforded a good opportunity to observe individual variations, and they do differ 
greatly. In length from 8 to 18 mm ; in pubescence, some being nearly naked and uni- 
colored, others having it longer and condensed into spots or almost vittate ; some 
being quite slender and elongate, while others are short and broad. The surface of 
the elytra is mostly uniform, but in some, especially such as are narrow and elon- 
gated, one or two costaB are more or less evident. 
Now, although this account differs so widely from that given by Mr. Fitch, still 
the beetles are the same. Unfortunately, I have never been able to find any pruned 
oak limbs from which to obtain the insects myself, but I have a good set from Mr. 
Blanchard, of Massachusetts, presumably from the oak, which are identical. Through, 
the kindness of Mr. F. Clarkson, I have a set of those described by him in the Can. 
Ent., vol. 17, p. 188, from oak limbs, and which became imagoes in November, and 
there is no perceptible difference. Dr. George H. Horn says, " They are the same." 
To identify Elaphidion parallelum had always been a puzzle to me, and I once thought 
I had a real set ; I obtained it about a dozen times by exchange, but could never be- 
satisfied that the specimens received were not pauperized or peculiar individuals of 
E. villosum. On comparing my hickory insects with all the descriptions of E. villosum 
and parallelum and their several synonyms, as far as I possess them, it was easy to 
pick out sets that would answer satisfactorily all their requirements, and I became 
satisfied that E. parallelum could not be separated. 
29. Elaphidion parallelum Newman. 
(Larva, PI. xvn, Fig. 1.) 
This borer, according to Riley, infests the oak, and Mr. Tyler Town- 
send, of Washington, D. C, has found it to be the common oak pruner 
of the vicinity of Constantine, Mich., while it also is common in hickory.* 
*Dr. Horn has, in a letter to Dr. Hamilton (Can. Ent., Aug., 1887), stated that 
Elaphidion villosum and parallelum " are inseparable." It is, however, too late, since 
this note is added in the galley proof, to combine the accounts of the latter so-called 
species with that of E. villosum. 
